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While thermoplastic polymers exhibit several desirable properties, their applicability is limited by their high viscosity and extreme processing conditions. To overcome these limitations, in this study, we used the thermoforming process to produce carbon fiber/polyetherketoneketone (CF/PEKK) laminates, which were pre-made through an oven-based consolidation process using prepregs. The laminates were produced at three different heating rates ($40^{\circ }$C/min, $75^{\circ }$C/min and $100^{\circ }$C/min). The laminates produced at the heating rate of $40^{\circ }$C/min showed improved interlaminar shear strength, $90^{\circ }$ tensile strength, and average interlaminar fracture toughness. On the other hand, heating at rates higher than $40^{\circ }$C/min increased the initiation value of the interlaminar fracture toughness ($G_{\mathrm{\text{IC}}-\mathrm{\text{I}}})$ but resulted in nonuniform composites of poor quality. This is because increasing the heating rate reduced the uniformity of the heat distribution with the laminates, resulting in the polymer molecules exhibiting different binding rates and thus nonuniform cross-linking. Thus, the proposed method is a suitable one for producing high-quality thermoplastic composites.

Ultrasonic tube forming is an innovative and promising technology that could replace the conventional thermoforming process for plastic automotive tubes. This process allows for the forming of extruded tubes four times faster, with a substantial increase in energy efficiency. This research focuses on the experimental study of this innovative process and its comparison to the conventional thermoforming in a hot air table. A prototype has been designed and assembled to study the main process variables that are significant to the forming result. A complete design of experiments (DOE) has been applied to quantify the effect of each process parameter, thereby obtaining a mathematical model that allows for the prediction of the curvature angle for a specific parameter combination. It has been concluded that the application of ultrasonic cycles, with short cooling cycles in between, is the best option, in comparison to a continuous application. The amplitude of vibration, ultrasonic time for the cycle, and number of cycles have proven to be the most significant variables of the process. Furthermore, the cooling time between cycles and the position of the squares for the initial bending angle are also important parameters that can be set up to refine the result. Quality control tests related to material degradation and geometry have been passed successfully, showing a high stability of the results. Consequently, this new process has a promising place in the future of plastic tube forming.

With the development of the demand for lightweight automobiles, in addition to improving the strength of car structure, how to increase the production efficiency of thermoforming lines has also become a focus of research. In the complex equipment and cumbersome production process of thermoforming process, the flexibility and speed of industrial manipulators had great influence on the compactness of the thermoforming line and the production cycle of the entire line, directly affecting the capacity and benefits of the entire thermoforming line. For the above problem, lightweight applications for manipulators in thermoforming lines have been put forward. A finite element analysis model with ANSYS workbench was built. The analysis and calculation of lightening for the Z-axis fixed joint of hearting furnace loading and unloading manipulator and the X-axis fixed joint of punch loading and unloading manipulator was done. The topology optimization for the Z-axis fixed joint was also done and the analysis and calculation for the optimized model was performed. The results show that when the performance and strength of the manipulator were satisfied, if the weight of the Z-axis fixed joint was reduced by 10.16 %, the transport time of the hot billet was shortened to 6.5∼7 s and shortened by 18.75 %∼22.22 %, which improved the speed and flexibility of the manipulator. And the lightweight manipulators have been put into production at a thermoforming company.